From Melissa B:
Rudolph the Red was a Viking. One day he was sitting with his wife, eating lunch, and he looked out the window. "Looks like it’s going to rain," he said. His wife looked out. "No way," she replied. Rudolph the Red stood and insisted, "Rudolph the Red knows rain, dear."

From Michael M:
When four of Santa's elves got sick, the trainee elves did not produce
toys as fast as the regular ones, and Santa began to feel the Pre-Christmas
pressure. Then Mrs. Claus told Santa her Mother was coming to visit, which
stressed Santa even more. When he went to harness the reindeer, he found
that three of them were about to give birth and two others had jumped the
fence and were out, Heaven knows where. Then when he began to load the
sleigh, one of the floorboards cracked, the toy bag fell to the ground and
all the toys were scattered. Frustrated, Santa went in the house for a cup
of apple cider and a shot of rum. When he went to the cupboard, he
discovered the elves had drunk all the cider and hidden the liquor. In his
frustration, he accidentally dropped the cider jug, and it broke into
hundreds of little glass pieces all over the kitchen floor. He went to get
the broom and found the mice had eaten all the straw off the end of the
broom. Just then the doorbell rang, and irritated Santa marched to the door,
yanked it open, and there stood a little angel with a great big Christmas
tree. The angel said very cheerfully, 'Merry Christmas, Santa. Isn't this a
lovely day? I have a beautiful tree for you. Where would you like me to
stick it?' And so began the tradition of the little angel on top of the
Christmas tree.

From Megan B:
Q: Where do gingerbread men sleep?
A: On cookie sheets!

Q: Why does Rudolph have an umbrella?
A: Because he's a rain-deer!

From anonymous:
Here is one I remember from my kidhood (told by a minister):

Did you hear they canceled Christmas?
Joseph confessed.

And then there's the song from the Smothers' Brothers:
You better not shout
you better not cry
you better not pout
I'm tellin' you why
Santa Claus is dead.

From Dan L:
Here's my favorite Christmas joke:

Q: What did one snowman say to the other snowman?
A: Do you smell carrots?

From Whitney A:
A man in Scotland calls his son in London the day before Christmas Eve and says, "I hate to ruin your day but I have to tell you that your mother and I are divorcing; forty-five years of misery is long enough".

"Dad, what are you talking about?'" the son screams.

"We can't stand the sight of each other any longer", the father says. "We're sick of each other and I'm sick of talking about this, so you can call your sister in Leeds and tell her".

Frantically, the son calls his sister, who explodes on the phone, "Like hell they're getting divorced", she shouts, "I'll take care of this".

She calls Scotland immediately and screams at her father, "You are NOT getting divorced. Don't do a single thing until I get there. I'm calling my brother back and we'll both be there tomorrow. Until then, don't do a thing, DO YOU HEAR ME?" and hangs up.

The old man hangs up his phone and turns to his wife.
"Done! They're coming for Christmas—and they're paying their own way."

Kenneth W. adds:
During the Christmas show, the child asked why the reindeer crossed the
road and answered "to get to the antler station." I have some insight into
this joke. Once I told my four-year-old daughter a joke I had heard on the
joke episode of A Prairie Home Companion. Possibly it was told by Paula
Poundstone: Why did the turtle cross the road? To get to the Shell station.

Whenever I ask this riddle to my daughter, she laughs, but I don't think
she understands that Shell is a gasoline company that sells its products at
Shell stations.. She simply thinks it funny for a turtle to go to a shell
station.

Then she starts to ask her own riddles that she invents based on the
animal station motif: Why did the chicken cross the road? To get to the egg
station. Why did the dog cross the road? Do get to the puppy station. It
goes on and on.

So when I heard that boy answer "to get to the antler station," I thought
that the Shell station joke must have taken hold among children everywhere,
and thus, he invented one of his own.